All keys in bucket

list_keys.py

#!/usr/bin/env python3

import sys

import boto3

S3 = boto3.resource("s3")


def list_keys(bucket_name, prefix=''):
    objs = S3.Bucket(bucket_name).objects
    for obj in objs.filter(Prefix=prefix):
        print(obj.key)

if __name__ == "__main__":
    if len(sys.argv) < 2:
        print("Usage: {} <bucket>".format(sys.argv[0]))
        exit(1)

    bucket = sys.argv[1]
    prefix = ''
    if len(sys.argv) == 3:
        prefix = sys.argv[2]

    list_keys(bucket, prefix)